The invention is in the field of mechanical engineering and precision engineering and relates to a pump device.
Pumps are used for conveying fluids, in particular liquids, and are known in a variety of variants. Pumps are particularly interesting for many applications which either have a particularly small construction or whose design is changeable to be taken to a place of deployment with difficult access in a transport state, wherein an expanded state or an operating state can afterward be established in which individual elements of the pump have a different shape and/or size than in the transport state.
Examples for such pumps are expandable catheter pumps which are introduced into a patient's body through a blood vessel and can be inserted up to and into a ventricle and can be expanded there.
For this purpose, an expanding of a rotor of the pump and of a housing typically takes place. The rotor usually carries one or more impeller blades which can be radially compressed and expanded alone or together with a hub. For this purpose, conveyor blades can, for example, be fastened flexibly or pivotably to a hub or can be configured as compressible by the manufacture as a foam body. Such conveyor blades occasionally also have portions made from a memory alloy such as nitinol which has super-elastic properties and temperature-dependent shape properties. A corresponding rotor is then radially compressible with a small force and erects itself independently again to its original shape at a suitable temperature after the removal of the compression force.
Principles are also known in accordance with which a corresponding pump is actively erected/expanded by actuation from the outside after the transport to the place of deployment (WO 94/05347 A1). Such constructions, however, require corresponding actuation devices and elements for transferring such an actuation, which requires an increased electric, pneumatic or mechanical effort.